1.Brood,litter refer to young creatures. Brood is especially applied to the young of fowls and birds hatched from eggs at one time and raised under their mother's care: a brood of young turkeys.Litter is applied to a group of young animals brought forth at a birth: a litter of kittens or pups.

"sit on eggs, hatch," mid-15c., from brood (n.). The figurative meaning ("to incubate in the mind") is first recorded 1570s, from notion of "nursing" one's anger, resentment, etc. Related: Brooded; brooding.